Load-handling attachment for lift trucks



June 10, 1952 w. lw. MlcHAUx, JR

June 10, 1952 w. w. MlcHAux, JR

LOAD-HANDLING ATTACHMENT FOR LIFT TRUCKS Filed April 17, 1950 2SHEETS-SHEET 2 IlI Patented June 10, 1952 y OFFICE n LOAD-HANDLINGATTACHMENT Fon LIFT TRUCKS william W. Michaux, Jr., Richmond, va.Apueation April 17, 195o, serial No. 156,340

Y l Claims. 1

In the handling of large heavy and bulky articles of generally uniformsize and shape such as hogsheads of tobacco. or rolls of newsprint, itis customary to use so-called lift trucks which are power-operatedtrucks incorporating hoisting or lifting mechanism. One form of such alift truck consists of a wheel-supported frame having normally verticalguide means on which a slide including normally horizontalarticle-supporting arms or forks is mounted. The power means, usually aninternal combustion engine carried by the frame, can be connected toelevate the slide along the aforesaid guide means irom one position inwhich' the article-supporting forks are closely adjacent the fIoor,-toanother position in which these forks are elevated severalr feet abovethe floor so that articles of the kind described can be convenientlyelevated for transportation from one location to another, for stacking,or other purposes. In the power-operated handling equipment justdescribed, the vertical guide means previously mentioned'is mounted uponthe frame for pivotal movement or tilting about a horizontal axis closeto the floor and normal to the vertical. guide surfaces andlto the'aforesaid forks. In using such equipment, for instance, to elevatehogsheads ofv tobacco from one level to another, asin stacking.the-truck is propelled forwardly until the `supporting forks are thrustbeneath the' hogshead.` The hoisting l mechanism is then clutched vin toelevate the forks and, substantially simultaneously, to pivot the guidemeans aboutits horizontal pivotaxis whereby the free ends of the forksare tiltedupwardly and gravity acts to hold the. hogshead from rollingoi the forks. After the hogshead has been elevated to the desiredheightand properly positioned, the guide means isrestored' to thevertical so that the hogshead either rolls ofi the now horizontal-forks'by itself or bythe application of a small force applied manually.

In the practice just described, difficulty is frequently encountered ingetting the forks fully beneath the hogshead. That is, the hogshead,unless prevented from se doing, may start to roll away from the truck'before the forks canbe tilted sufficiently to hold itin positionthereon. Furthermore the tilting of the guide means or columns togetherwith their forks, is a,time

consuming operation amountingto a large loss in the course of handlinghundreds or thousands of articles.-

Y It is therefore the Iprincipal object of my invention to provideadevice in the natureof an attachment for hoisting andhandling equipmentof the type, described, particularly lift trucks,

wherein the objectionsand drawbacks enumerated are overcome andobviated.

More particularly, it is the purpose of my nvention. to provide anattachment which as the forks are thrust beneath an object to be moved,automatically operates in response to engagement with the object topositively secure the object on the forks and to prevent it from rollingor sliding thereof'f.

Another object is the provision of an attachment as described which, bysecuring the hogshead or other object upon the supporting forks, makesyit unnecessary to tilt the guide columns or mast upon whichthe loadcarriage is mounted for translation. Indeed, where a lift truck is builtsolely for rhandling of articles or objects of the type described, thetilting mechanism may be eliminated with a corresponding substantialrreduction in initial cost of the equipment.

A still further object is the provision of an attachment as describedwhich is relatively simple and inexpensive to construct, positive inoperation, and which may be easily applied and attached toexisting lifttrucks as Well as embodied in trucks to be built.

yAnother object is toprovide a mechanism as described which is positiveand. automatic in operation in securing in position upon the forks, anobject or article being transported and one whichis easilyV and simplyreleased when the object or article isto be deposited.

Yet another object is to provide al combined lift truck andarticle-securing attachment thereforewhich permits the elimination ofcomplicated l and expensive parts of the truck while retaining all thefunctionsof prior art lift trucks.

Other objects and advantages will be apparent to those skilled in theart after a study of the followingdetailed description in connectionwith the accompanying drawings.

In the drawings:

Figure 1 is a side elevation showing, a lift truck equipped withv myinvention and, in dotted lines, the position of the partsjwhen the truckhas been operated to raise a hogshead of tobacco to'substantiallymaximum elevation. Y

Figure 2 is a plan view to an enlargedscale of the lift, portion of atruckequipped with the invention, the tine or article-engagingl partybeing shown-in; forward or unlocked position.

Figure 3. is a detail sectional View on line 3 3, Figurer 2, and tolanenlarged scala-of the rearwardv portion of the support bar. and lockingslide, theparts being in a position`of the tine corresponding; to FigureY2.

Y with the axis of wheels 3.

but showing the slide bar in position locking the tine in position tosecure an article on the lift forks.

Figure 5 is a view corresponding to Figure 4 but showing the end of thelocking slide in raised position to unlock the same.

Figure 6 is a side elevation of the support arm and tine, the latterbeing in locked position, and

Figure 7 is a cross section on the linel--l of Figure 3.

Referring in detail to the drawing, and particularly to Figure 1, thenumeral I identies generally a well-known type of power operated lifttruck comprising a body 2 supported for rolling movement bytwo-power-driven wheels 3 and a steering wheel 4. The body has aplatform Elon which the operator stands to operate steering wheel 6 andcontrol levers, one of which is indicated at 1. The lift guide or framecomprises generally a pair of spaced generally vertical beams of mastsrigidly connected in spaced parallel'relation. One of these beams isshown at 8.

` This frame is pivoted to body for angular movement about a horizontalaxis generally coincident A power-operated lever 9 is pivoted at one endto the lift frame and is retractible by power-operated mechanism, notshown, lto pivot the frame and load-supporting slide |0 about theaforesaid axis from the position shown upon Figure 1 to a position inwhich the frame 8 is tilted rearwardly a few degrees.

The slide I0 has interconnected elongated slide members, each guided forvertical translation by the .channels of frame 8. Such translation iseffected by well-known mechanism including chains A pair of lift forksI2 and I3 (see Figures l and 2), are fixed to the lower portion of slideI0 in parallel spaced relation to the oor when the slide is in lowermostposition. A prime mover, usually an internal combustion engine, ismounted in body 2 and can be connected by suitable control levers suchas 'I to propel the truck, elevate the slide I0 and tilt the frame 8.

The mechanism described in the preceding paragraphs is well known and,apart from the combination,V forms no part of my invention, now to bedescribed. The load supporting slide ID has a carriage guard Illarigidly connected with the slide. To the uppermost horizontal member ofthis guard, I Vattach in spaced relation therealong, a pair of bracketsI4 and I5, Figure 2, in which a shaft I6 is journaled in horizontalposition. A forwardly-extending arm I1 is fixed at one end upon shaft I6adjacent bracket I4. See Figures 3 and 4. A brace bar I8 is fixed at oneend to arm and at its other end to shaft I6 adjacent bracket |-5, toimpart rigidity to the arm. As shown upon Figure 7, the arm may lberectangular in cross section. By this construction, the arm is mountedfor swinging in a vertical plane about the axis of shaft I6, from thegenerally horizontal position shown at Figure 1,

to a vertical position. A bracket 20, is fixed to a portion of the.carriage guard IUa, to limit downward pivotal movement of arm to the ihorizontal position shown.

A tine 2| of the general shape shown in Figure 6, has a longitudinalslot 22 formed in its central portion of a width sufficient .toaccommodate the end of arm with a smooth fit. A .pin 23 passes throughthe tine and arm to pivotally connect them whereby the tine may pivotfrom the loading position of Figure 1, to the locking position ofFigureY 6. Clockwise-movement from the loading position is limited byen- L.

gagement of the corner 22a of the slot with the top surface of arm I1.This limit position is about as shown in Figure 1 in solid lines.

A channel locking bar 24 has a sliding fit over the arm and extendstherealong from a point somewhat rearwardly of tine 2 I, as shown inFigure 1, to a point a little forwardly of shaft I6. The forward end ofthe locking bar has a strap portion 24a extending downwardly and aboutthe arm I`| whereby this end of the bar is limited substantially tosliding movement along the arm. This end of the bar also has an upwardlyoffset portion A2,417. A pair of links 25 and 25 (see -Figures 2 and 6)are connected by a common pivot pin 2l with the forward or load-engagingend of tine 2| while another common pivot pin 28 connects these linkswith portion 24h of bar 24. By this construction, the locking bar is inthe forward position of Figure 1 when the tine extends forwardly and inthe rearward position of Figure 6 when the tine extends rearwardly inlocked position.

The rearward end of bar 24 has a strap portion 24o extending downwardlyand about arm I1. As seen in Figure 7, there is a substantial clearancebetween the strap and arm so that the bar, at this end, may be movedupwardly a short distance. This end of channel or bar 24 has a raised orupwardly inclined cam portion 24d and an aperture 29 adapted to dropover pawl I9 :fixed with arm I'| as the bar moves into locked position.Thus, as the locking bar slides rearwardly on arm in response toswinging of tine 2| from forward position to locking position, camportion 24d rides up on pawl I9. and, in the final locking position oftine 2|, bar 24 drops over pawl I9 to hold positively or lock the tinein final position. A pair of links 30, one of which is sho-wn at Figures3, 4 and 5, has spaced apertures. Shaft I6 Y passes through thelowermost of these apertures and each link is rigidly secured to theshaft as by welding or set screws.V A release rod 3| is journaled in thesecond or upper apertures of links 30 and is xed against axialv movementas by collars. At its portion in alignment with cam portion 24d, rod 3|has a release lug 32 fixed thereto so that when the parts are in the.locking position of Figure 4, cam portion24d lies directly over lug 32.Then when shaft 3| is pivoted clockwise to the position of Figure 5, lug32 lifts the adjacent end of locking bar 24 until itv clears latch I9 tothereby free the tine formovement to forward or article-releasingposition. An operating lever 33 is fixed to the left end of rod 3 I.

For operating lever 33 clockwise to release the bar 24-from pawl I9 Ihave provided a vertical tube 34 positioned at the right of the operatorwhen he is in positionupon'platforr'n 5.' This tube has a pulley 35fixed at its top.' Aweight 42 slides within the tube and is connected bya cord or rope 36 with lever 33.' As 'shown'at Figure 1, this cord hasone end attachedV to 'lever`33 and then passes downwardly about-aVpulley Y3'! attached to a bracket carried slideIiL then upwardy over andabout a pulley V38 'carried Vat the top of the frame o r mast l8andthericein a horizontal -pass to pulley 35. Thisrhoriz'ontalpasstherefore at all 'times extends 'diagonally across and in front of theoperatorfaiid is always'in the same convenient position. As the-load-supp'orting slide I0 is elevated by chainsY |'I"urile1f' drivefrom the motor of the truck, the weight within tube a4 slides thereinand acts tokeep the cora Y 36 taut.l A- second pulley BBQ-is'munted atthe Vpulleycti Asthe'slide-is elevated and pulley 31 vmoves above pulley38,- the cord 36 then extends 4from vthe horizontal pass underi andupwardly about pulley 38a, asindicated in dotted lines upon Figurel. f Y

For the purpose of resiliently and yieldingly holding the rearward endof bar24 upon-arm- I'I, a rod'39 is fixed at oneend to-shaft 3I. Theother end of Ithis shaft is bent at 90 and has a; roller 4l)"jou'rnaledthereon in position to contact the upper surface of vbar 24. A tensioncoil spring 4I is. secured at oneend tov rod 39 and atthe other end tothe adjacent side offarfn I1 and thus acts to: urge' the roller'downupon bar 24'- and to yieldinglyV lfi'oldv the bar uponarm I'I unless anduntil released by a pull on-cord 36. Spring'III also'l acts to hold4lever 33 in the inactive position shown upon Figure l.

In operation, the Atruck with parts as shown in Figure l',` is propelledtoward a hogsh-ead H of tobacco.` As the grippingend of tine 2| contactsthe upper portion of the hogshead, the tine is pivoted rearwardly whileat the same time the arm I'I, bar 24 and parts attached' thereto, maypivot upwardly slightly about thev axis of shaft I 6. The parts are soproportioned and dimensioned that forks I2 and I3 are fully positionedbeneath the hogshead shortly after the instant that Ybar 24 drops intolocking position over pawl I9. vThe parts arethen substantially as shownin the dotted line position of Figure 1 whereby the hogshead is securelyheld against rolling off the supporting forks. The lift slide may thenbe operated to'raise the hogsheadto the desired or necessary height.When it is desired to release the hogshead, the operator merely reachesup and pulls upon the horizontalv pass of cord 36 to pivot lug 32andthereby effect release'of bar 24 in the manner obvious frominspection of Figure 5. Of course, the invention is equally useful whenthe truck is being used to remove hogsheads from a stack thereof to thefloor.

While, for the purpose of complying with the patent statutes, I havedescribed the device in connection with the handling of hogsheads oftobacco, it will be understood that, as already intimated, the inventionis not limited to such use but can be readily adapted for handling rollsof newsprint, barrels, kegs, drums and other articles of regular orirregular shape. Hence the foregoing description is to be taken in anillustrative rather than a limiting sense; and it is my desire andintention to reserve all substitutions and modifications falling within`the scope of the subjoined claims.

In the claims, the terms load-release and load securing positions asreferred to the tine 2| means the respective positions thereof in whichthe tine releases and secures a load upon the forks I2 and I3.

Where articles are being handled which might be damaged by the use of apointed tine as shown, such for example, as rolls of newsprint, a tineequipped With a tip of rubber or other frictional material will besubstituted.

Having now fully disclosed th-e invention, what I claim and desire tosecure by Letters Patent is:

l. The combination with the vertically movable slide and load-liftingfork of a lift truck, of a normally horizontal arm carried by said slideabove said fork and having a latch at one end, a tine pivoted to saidarm at the other end thereof, a bar slidable on said arm, a link pivotedat its ends to said tine and bar, respectively, whereby said bar istranslated along said arm in `response tovp'ivoting. of said tine,andfmeansion l'said arm releasably engaging said latchwh'en said ltineextends downwardly and rearwardlytowardsaid latch.

2. -In combination,- a vertically movable sli'd'e of ay lift truck, aload-lifting fork carried said slide and extending horizontallytherefrom ka normally horizontal arm pivoted on said slide labove andover said fork, said arm having a latchadjacent one end, atinep'ivoted-vto said-arm at the other end thereof, a barv carriedbysai'd arm, means mounting the 'endof said bar' adjacent said tine forslidingrr only on and alongl said arm, a link connecting said end ofythe bar and tine,

'whereby said .bar-slides uponV saidl r'e'- sponse to pivotingy offsaidtine,- m'eans mounting the other' end of said bar forslidi'ng and/orlat'- eral movement relatively to nsai-d arm, and means carried by saidother end-of the" bar' for cooperation with' said latchto automaticallylock said bar inV position corresponding to a load-securing position ofsaidtinerelatively to said-arm.'A

3. In combination, a vertically movable' power- .operated slide for aliftl truck, aglad mtmgfrk carried by said slide, anarm above andextendingI oversaid forkv in generally parallel, vertically-spacedrelation therewith, a tine connected with said arm at oneend thereof formovement from a first position releasi'ng'a'. load on'said fork to asecond position securing a.I load thereon, bar means carried by saidarmandconnected with said' tine at one end thereof for movement from firstto second position relatively to saidarm, by

landin response-to corresponding movement of said tine, and latch meansoperable automatically as said bar means moves intosecond position topositively lock said'ba'rvmeans and tine in their second positions.

4. In a device to secure a load upon the forks of a lift truck, a shaft,an arm fixed at one end to said shaft at right angles thereto, aload-engaging tine pivoted on said arm at the other end thereof, a barcarried by said arm and substantially coextensive therewith, meansmounting the end of said bar adjacent said tine for translation only onand along said arm, link means pivotally connected at one end with saidtine and at its other end with the adjacent end of said bar, wherebysaid bar is slid along said arm from first to second positions inresponse to movement of said tine on said arm from load-releasing toloadsecuring positions, respectively, latch means between said arm andbar adjacent said shaft and operable automatically in response tomovement of said bar to second position to lock the same in secondposition, bracket means fixed to said shaft, a rod journaled in saidbracket means parallel with said shaft, and latch release means carriedby said rod and operated by pivotal movement thereof to release saidlatch means.

5. A device as recited in claim 4, said bar being adapted for lateralmovement relatively to said arm at its end adjacent the shaft to releasesaid latch means, and a lug carried by said rod to engage and solaterally move said bar and release said latch in response to pivotalmovement of said rod.

6. A device as recited in claim 5, a lever fixed to said rod and havingone end extending over said bar, and spring means urging said lever intocontact with said bar to hold the same in engagement with said arm.

7. For use in a lift truck having a vertically movable slide and anormally horizontal elongated arm pivoted at its inner end to said slideon an. axis normal thereto, a tine pivoted to said arm atthe outer endthereof, for pivotal movement from a first position extending forwardlyand downwardly with respect to said arm, to a second position extendingrearwardly and downwardly with respect to said arm, a locking barYpivoted at its outer end to said tine and slidable along said arm inresponse to movement of said tine between rst and second positions,detent means carried by the inner ends of said arm and bar andautomatically operable in response to movement of said tine into secondposition to lock the same in said second position.

8. In a device of the type described, a vertically movable slide of alift truck having load-supporting fork projecting therefrom, an armpivoted at one end on said slide above said fork in normally parallelrelation therewith, tine means carried by said arm at the other endthereof above said fork and pivotable thereon from a load-releasing d toa vload-securing position. a bar slidable on and valong said arm, linkmeans connecting one end of said bar with said tine for sliding said barfrom a rst to a second Vlimiting position in response to pivotalmovement of said tine from load-releasing to load-securing position, alatch xed on said arm adjacent the pivot thereof, and

means carried by said bar to engage said latch Vand releasable lock saidbar relatively to said arm as the bar moves into second position.

9. The combination with a lift truck having a slide guided for verticalmovement and a pair of normally horizontal load-supporting forks xed tosaid slide, of an arm carried by said slide in vertically spacedparallel relation with, and above said forks, aV tine pivoted to theouter end of said arm and pivotable thereon from a forward and downwardrelease position to a rearward and downward, article-retainingposition,a lock bar pivoted at one end to said tine and longitudinally slidableon and along said arm, and means operable automatically to lock said barto said arm in response to pivotal movement of said tine to releaseposition.

10. In combination with a hoisting and handling mechanism having avertical slide and article-supporting means guided for'translation onand along said slide, an arm pivoted on said slide above and in spacedgenerally parallel relation with the article-supporting means,articleengaging means carriedV by said arm at the end thereof andmovable in response to engagement with an article as it moves onto saidarticle-supporting means, from article-release position toarticle-locking position, means automatically operable to releasablylock said article-engaging means vin locking position, and manuallyoperable means to release said locking means.

WILLIAM W. MICHAUX, JR.k

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

